This invention relates to electrical terminal connectors or lugs, and more particularly to solderless terminal connectors of the heavy duty type for use with copper or aluminum cables and which are connectable to electrical cables by a crimping process.
Prior terminal connectors which are connectable to cables by a crimping process have been formed by forging or casting processes or by a combined impacting and forging process.
Connectors formed by the forging process have a pad forged at one end of a piece of tubular stock. A draft or slope results at the transitional section between the tubular portion and the pad and a tapered cavity exists within the transitional section. Because a sealing compound is generally put into the opening in tubular portion before inserting a cable, the tapered cavity requires that an additional and wasted amount of sealing compound be added to fill this dead volume in order to insure that the compound will make adequate contact with the cable.
Prior connectors formed by casting or by the combined impacting and forging process also have a draft or slope at the transitional section between the body portion and the pad. The draft is required in the cast connectors to permit the pattern to be withdrawn from the mold. Although the draft at the transitional section may be eliminated in a cast connector, a draft will then be required at other ninety degree corners, such as on the pad. In the combined impacting and forging process, a tubular body portion is first impacted out of one end of a length of solid cylindrical stock. A pad is then forged at the other end. The transitional section between the body portion and the pad necessarily has a relatively large draft or slope in order to prevent deformation of the tubular portion or shearing at the closed end of the tubular portion during the forging of the pad. Unlike the forged connectors made from tubular stock, cast or impacted and forged connectors have a solid metal transitional section.
The terminal connectors of the crimp type formed by the above processes are longer than necessary from an electrical standpoint because of the sloping transitional section between the tubular portion and the pad. The sloping configuration of the transitional section is not electrically functional and adds considerable undesired length to the connector. This additional length renders such terminal connectors difficult to install in applications having limited space and unsuitable for use in industrial control equipment designed for the use of terminal connectors in which the cables are clamped by means of one or more screws. Furthermore, the existing connectors have a surplus of metal at the transitional section.
A need exists for an electrical terminal connector of the crimp type having a transitional section between the pad and the tubular portion that adds no length to the connector, which includes no wasted metal, and which still has adequate current carrying capacity throughout its length.